Rigid airship



g- 13, 1929- B. N. WALLIS ET AL I 1,724,440

RIGID AIRSHIP Filed Aug. 19, 1927 2 Sheets-Sheet l Au 13, 1929. B. N. WALLIS'ET AL RIGID AIRSHIP 2 Sheets-Sheet 2 Filed Aug. 19, 1927 retiree Aug. is, 1929.

BARNES NEVILLE 'WALLIS AND C ENGLAND, ASSIG-NOES T0 AIR-i wasps DENNISTON BURNEY, OF WESTMINSTER, .E GUARANTEE COMPANY, IVIINST EB, ENGLAND, A BEETISH COMPANY.

RIGID AIR-SHIP.

Application filed August 19, 12327, Serial No. 214,028, and in Great Britain September 17, 1926.

This invention relates to rigid airships of the kind which comprise longitudinal girders extending from the bow to the stern of the ship and transverse frames which intersect the longitudinal girders at intervals and which frames are usually of the form of polygonal rings.

In the past it has not been possible to revolve or determine in an accurate manner the various forces acting at different points throughout the framework of an airship and the latter has accordingly been more or less of a redundant structure comprising a large number of relatively small members which have been interconnected in such a manner that the forces set up are distributed indeterminately throughout the component parts of the structure. As the exact nature of the forces acting on any particular member or group of members in a highly redundant structure can only be estimated with an approximate degree of exactitude, it has been impossible to reduce their weight to the inimum while preserving any required .factor of safety.

The object of the present invention is to reduce to the minimum the number of component parts in the structural framework of an airship and, by an equal or proportional distribution of the load throughout the members of a framework specially designed to support it,,to secure a reduction in weight and produce a simplified structure in which any necessary factors of safety which it is desired to obtain in each com ponent part ca'nbe predetermined with ere actitude.

In order to obtain this result it is necessary in the first instance to ensure an equal distribution of the forces throughout constituent parts of the longitudinal girders and the transverse frame members so that no undue stresses or bending moments arise and to this end and according to the present invention the centroid of each transverse frame member as also that of the intersecting longitudinal girders are made coincident or approximately coincident at a point. lhe lift wires and shear wires alone, together in certain cases with the transverse bracing wires or bulkhead wiring, are connectedfto, or approximately to, the point of coincidence of the centroids of the intersecting frames and girders. According to one arrangement lair is mounted.

threaded collars.

vbuilt into and secured to the transverse mivirrnn, 0F wnsn' frames with their centroids coincident with those ofthe transverse frame, the point of intersect-ion forming the centre of, a structure the extremities of which lie on the surface of an imaginary sphere or spheres.

In previous systems, it has been common to make connections from the mesh wiring which supports and encloses the gas containers direct to the longitudinal members,

from whence the lifting forces were in turn transferred to the transversevframe members. Owing torthe' fact that the'load is transferred to the longitudinal membersas a beam it is difficult in this system to estimate the stresses set up in the framework.

In order to secure a more direct application of the lifting forces to the framework of the airship it is proposed to attach the mesh wiringto the framework at the points of intersection of the longitudinal girders and the transverse frames. 7 i i In cases,for example, where the longitudinal girders are of triangular cross section, each corner of the triangle being constituted by a tube, a member (hereinafter termed a longitudinal spider) may be providcd having three radial arms, each arm being, provided at its outer extremity with a semi-circular socket which accommodates a tubular socket piece projecting laterally on each side of the spider.

pieces on the spider the ends of a pair of contiguous girder sections can be detachably secured to the sockets on the spider by means of the aforesaid internally screw The base of each triangular transverse frame membeiywhereat each corner of the polygon the frame is intersected by the longitudinal girder, is secured to the longitudinal'spider by a corre- Each end of the 1 socket; piece isprovided with a screw thread incident with the centroid of the longitudinal girder. To restrain angular displacement of the transverse spider relatively to the longitudinal spider the transverse spider may be connected to the longitudinal spider at two points.

In order that the said invention may be clearly understood and readily carried into effect, the same will now be described more fully with reference to the accompanying drawings, in which Figure 1 is a section through one of the transverse frame members of an airshlp at the point where the said frame lntersects a longitudinal girder, the transverse frame members being of triangular cross-section with the apex pointing inwards towards the centre ofthe ship, and the longitudinal girders being of triangular cross-section with the apex pointing outwards.

Figure 2 is a sectional end view of Figure 1.

Figure 3 shows a suitable form of coupling device for attaching the shear and lift wires to the centroid of the longitudinal spider, and I Figure 4 is a section on the line 44 of Figure 3.

Fig. 5 is a perspective view of the combined longitudinal and transverse spiders, and

Fig. 6 is a view of a portion of a transverse frame with the adjacent circumferential wiring to illustrate the position and function of the lift and shear wires, the longitudinal members and bulkhead Wiring being omitted for the sake of clearness.

The longitudinal girders and the transverse frame members are of triangular cross-section as aforesaid, each corner of the triangle being constituted by a tube, and the tubes being interconnected by means of bracing members (not shown). A, A, are

the tubes forming part of the longitudinal girder and B, B are the tubular corner members of the transverse frame. The longitudinal spider has three radial arms G, C, C, attached at their inner ends to a triangular connecting piece C each arm being provided at its outer extremity with a semi-circular socket C which accommodates a tubular socket. piece 0 projecting laterally on each side of the spider. Each end of each socket piece C is provided with a screw thread on which an internally screw threaded collar C is mounted. The ends of the tubular members A, A, of each secspider C by means of the aforesaid internally screw threaded collars The transverse spider is of triangulated configuration with the apex pointing inwards to wards the axis of the ship and comprises three members E, E, E, the ends of which are located within three sockets E, E, E, each socket E carrying a tubular socket piece E projecting laterally on each side of the spider E. Each end of each socket piece E is provided with a screw thread on which an internally screw threaded collar E is mounted. The ends of the tubular members B, B, of each section of the transverse frame members are provided with screw threads and, by bringing them into alignment with the socket pieces E E on the spider E, the ends of a pair of contiguous transverse members canbe detachably secured to the socket pieces E E by means of the screw threaded collars E E As' indicated, one of the members E is cut in order to permit one of the arms C to pass through it, the portions of the member E being connected by side plates E The longitudinal spiderC and the transverse spider E are secured to one another so thattheir centroids coincide at the point P. To restrain angular displacement of the transverse spider E relatively to the longitudinal spider C the former is secured to the latter at two points F and F. In order to provide a degree of angular flexibility between the longitudinal girders A, A and the frame members B, B, the connections between the longitudinal and transverse spiders may be made sufliciently flexible by such means asv vided the same vertical relationship of the intersecting parts is not altered. The point of intersection of the centroids is arranged so that it occurs at the axis of the longitudinal spider and at this point, an axial opening C is provided throughwhich end pieces G, G for the lift wires, and end pieces H, H for the shear wires are passed, the said end pieces being secured in position by a coupling device. A suitable form of coupling device is illustrated at Figures 3 and 4 and comprises a sleeve I to beiitted within the apertures C and through which the/end pieces G, G and H, H for the lift and shear wires G and H are threaded, the wires being secured in place within the sleeve for example by means of swaging or of soft .met-al J which is poured around the wires and allowed to set. Alternatively soft metal may be compressed around the wires or the wires may be secured in position by means of a bolt carrying suitable fork ends for the reception of similar ends attached to the main cables. At each of their ends the said end pieces G, G and H, H carry turnbuckles to which the lift' wires G and the shear wires H are attached.

The aforesaid arrangement may be used in conjunction with'the system of mesh wiring described in Patent No. 1,658,821 and/or the system of bulkhead wiring described in co-pending patent application Serial No. 214,036, filed August 18, 1927 where a strop connects the bulkhead wiring to the point of attachment of the circumferential mesh wiring, and/or with the system of bulkhead wiring described in co-pending application Serial No. 214,328 filed August 28, 1927, where the said wiring comprises taut and slack wires together with an axial restraint. In the embodiment illustrated L, L (Figures 1 and 2) are the slack catenary wires and M is one of the taut radial wires of the said bulkhead wiring described in application Serial No. 214,328 filed August 20, 1927, and N, N (Figures 1 and 6) are the strops for connecting the bulkhead wiring to the circumferential mesh wiring as described in application Serial No. 214,036 filed August 18,1927.

As will be seen from Fig. 6, the lift wires G the function of which is to transfer the buoyancy of the gas bags contained within the circumferential wiring to the rigid members of the structure, are attached to the points where the strops N join the circumferential wiring and pass immediately of their length, by junction with the end pieces G, Figures 1 to 4, through the centroids P of the transverse members. Similarly the shear wires H by means of end pieces H, pass from the centroids in one transverse frame to those in the next, being crossed as indicated in Fig. 6 in order to brace the panels formed by the longitudinal and transverse frames.

In cases where the apex of each longitudinal girder points outwards as in the ex.

ample illustrated the method of securing the outer cover in place, involving the use of tension wiring as described in English Patent No. 282,518, can also advantageously be employed either alone or in combination with the arrangement described in English Patent No. 280,670 where each panel of the outer cover is detachably secured to the intersecting points of the longitudinal girders and transverse frames by means of catenaries.

What we claim and desire to secure by Letters Patent of the United States is '1. A rigid airship in which the centroids of the transverse frame membersand of the res ectivel intersectin lon itudinal-girdy 3 b b ers are made substantially coincident at a point, and lift wires and shear wires are connected to the intersecting transverse frame members and V longitudinal girders substantially at the said points of coincidence. i I

2. A rigid airship in which the longitudinal girders and the transverse frame members are of triangular cross section, the apex of the longitudinal girders and the apex of the transverse frame members pointing in opposite directions and wherein, at

tudinal girders substantially at the said' points of coincidence.

3. A rigid airship as claimed in claim 1, v

wherein intersecting longitudinal and trans verse spiders having substantially coincident centroids are provided to which the longitudinal girders and the transverse frame members are attached.

4:. A combined longitudinal and trans verse spider for connecting the corresponding members in a rigid airship, wherein the longitudinal spider structure has three radial arms, each arm being provided-at its outer extremity with a tubular socket piece projecting laterally on each side of the spider to which the ends of the tubular portions of the longitudinal girders are attached.

5. A combined longitudinal and transverse spider for connecting the correspond ing members in a rigid airship wherein the transverse spider structure is constituted by a triangulated structure which is attached, preferably in a flexible manner, to the longitudinal spider, the tubular end members of the transverse frame members being connected to socket pieces carried by the said transverse spider.

6. A combined longitudinal and transverse spider for'connecting the corresponding members in a rigid airship, wherein the longitudinal spider structure has three radial arms and the transverse spider structure is constituted by a triangular frame the plane of which is at right-angles tothat of the arms.

7. A combined longitudinal and trans- I verse spider for connecting the corresponding members in a rigid airship as 1n claim 6, in which one of the radlal arms projects through one of the sides of the triangular ing members in a rigid airship as in claim 6, in hich the centroids of the longitudinal and transverse spider structures are coincident.

9[ A rigid airship as claimed in claim 1, provided with longitudinal and transverse spiders and in Which the bulkhead Wiring is attached to the apex of the transverse spider.

10. A rigid airship as claimed in claim 1, 10

necting the bulkhead Wiring to the circum-.

ferential mesh Wiring.

BARNES NEVILLE WALLIS. CHARLES DENNISTON BURNEY. 

